将目录中小写文件名改成大写文件名

#!/bin/sh
dir="/mnt/shell"
files=`find $dir -type f`
for i in $files
do
dir_name=`dirname $i`
ori_filename=`basename $i`
new_filename=`echo $ori_filename | tr [:lower:] [:upper:]` > /dev/null
echo $new_filename
mv $dir_name/$ori_filename $dir_name/$new_filename
done